Analysis Of Experimental Data For Two-Band Superconductors At T Approximate To T-C Using The Gl Theory In The Presence Of A Self-Consistent Vortex Line

We study the two-component Ginzburg-Landau (GL) theory, in the presence of a self-consistent vortex line, to obtain the penetration depth (lambda) and the effective healing length (xi), in the asymptotic limit r ->infinity. All these parameters versus T/T-c are analyzed for the materials MgB2, V3Si and LiFeAs in the interval 0.88 <= T/T-c <= 1.0, where the GL theory is assumed to be valid. We find that kappa = lambda/xi, which is another parameter not related to the GL parameter, is T-independent for V3Si and LiFeAs, while is T-dependent for the compound MgB2. This result suggests that even though all these three materials display two-gap superconductivity overall, near T-c superconductivity in V3Si and LiFeAs seems to be different from the one in MgB2. The use of this parameter, kappa, as a new way to "study" the superconducting materials, under the presence of a single vortex, is valid for 0.88T(c) less than or similar to T <= Tc, namely, in the GL formalism.